Objective:

Our current understanding of the ultimate health effects of engineered carbon nanomaterials is limited because exposure assessment, pharmacokinetic, epidemiological, and toxicological studies of these nanomaterials are in the nascent stages of analysis or have not yet been performed. Recent toxicological studies of single wall carbon nanotubes have indicated that long, fibrous nanotubes may exhibit abestiform behavior and cause adverse pulmonary outcomes. However, the estimated exposure to carboneous nanomaterials in the workplace is relatively unknown, which complicates assessing risk in the workplace. Using data from the National Institute for Occupational Safety and Health (NIOSH) Nanotechnology Field Team Studies, this project will focus on occupational exposure analysis in industries and research labs involving carbon nanotubes and carbon nanofibers.

The objective of this study is to analyze carbonaceous nanomaterial exposure scenarios, to identify knowledge gaps in carbon nanomaterial exposure assessment, and to predict and rank task-specific exposure estimates. The information gathered will be important for nanotechnology risk assessment and animal-human lung dosimetry models.

Approach:

The research will involve identifying and defining the processes of carbon nanotube and nanofiber synthesis, characterization, purification, and manipulation in order to create a specific occupational task exposure matrix. Micro environmental modeling and sensitivity analysis will be used to make statistical exposure estimates based on carbonaceous nanoparticle emissions data.

Expected Results:

It is expected that the findings from this study will contribute to human exposure estimation during the product lifecycle analysis of carbon nanotubes and nanofibers. In addition, the task exposure matrix will provide important background information for the design of future occupational epidemiology, risk assessment, and environmental exposure studies of nanoparticles.

Supplemental Keywords:

Progress and Final Reports:

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.